Abstract
The endangered smooth coneflower is native to the southeastern piedmont, where its habitat depends upon regular fire regimes. This analysis of the impact of changes in the light environment on biomass allocation and photosynthetic performance involved raising plants under three light regimes (18%, 43%, and 100% sunlight) for six months. There were no significant differences in photosynthetic responses between plants grown under different light regimes. This indicates that the species continues the photosynthetic responses of sun-grown plants even when grown under low light conditions. However, plants grown under low light conditions had lower root and stem dry weight and fewer flower heads than those grown in medium or full light.